add small helper to scalar range

framework/random/src/mm/random/srng.hpp

@@ -7,7 +7,7 @@ namespace MM::Random {
 
 // Seeded (Pseudo-) Random Number Generator
 struct SRNG {
-	// make shuffle compat 
+	// make shuffle compat
 	// TODO: add more type info
 	using result_type = uint32_t;
 
@@ -35,7 +35,7 @@ struct SRNG {
 	}
 
 	bool roll(float prob) {
-		return zeroToOne() <= prob;
+		return zeroToOne() <= prob; // TODO: just < ?
 	}
 
 	// more advanced

framework/std_utils/src/mm/scalar_range2.hpp

@@ -60,6 +60,16 @@ struct ScalarRange2 {
 	[[nodiscard]] constexpr bool inRange(T&& value) const {
 		return value >= min() && value <= max();
 	}
+
+	// lerp between min and max
+	[[nodiscard]] constexpr T map(const float a) const {
+		return min() * (1.f-a) + max() * a;
+	}
+
+	// reverse map
+	[[nodiscard]] constexpr float unmap(const T& v) const {
+		return (v - min()) / static_cast<float>(max() - min());
+	}
 };
 
 } // MM